Silo door construction

ABSTRACT

A frame adapted to be mounted in a door opening in a silo wall, the opening extending for the greater part of the height of the silo wall, the frame including side members defining opposed guide elements. An elongated flexible door is movable in the guide elements longitudinally of the silo wall opening between open and closed positions, and means is provided for imparting opening and closing movements to the door.

United States Patent [1 1 Koser 1 Dec. 11, 1973 SILO DOOR CONSTRUCTION [76] Inventor: Robert F. Koser, Almena, Wis.

[22] Filed: Aug. 28, 1972 [21] Appl. No.: 284,365

[52] US. Cl 52/196, 160/265, 160/271 [51] Int. Cl E04h 7/22 [58] Field of Search 160/271, 272, 265,

[56] References Cited UNITED STATES PATENTS 6/1941 Vollberg et al. 160/265 X 7/1934 Converse 160/265 X 3/1969 Pierce 160/271 X 5/1958 Rutten 52/196 X 5/1970 Sivin et al. 160/310 UX 9/1971 Koser 52/248 X Primary Examiner-Mervin Stein Assistant ExaminerPhilip C. Kannan Attorney-Ralph F. Merchant et al.

[57] ABSTRACT A frame adapted to be mounted in a door opening in a silo wall, the opening extending for the greater part of the height of the silo wall, the frame including side members defining opposed guide elements. An elongated flexible door is movable in the guide elements longitudinally of the silo wall opening between open and closed positions, and means is provided for imparting opening and closing movements to the door.

2 Claims, 3 Drawing Figures SILO noon CONSTRUCTION BACKGROUND OF THE INVENTION Silos having vertically elongated openings in the side walls thereof, for unloading silage therethrough from the inside of the silos, are known, these openings normally being closed by superposed door sections that are removed successively as the silage is discharged from the silo. Removal of the door sections is a rather laborious task, usually requiring the operator to climb a ladder-like structure to the level of the topmost section, and manually removing one or more sections. This operation is repeated until substantially all of the door sections are removed and the silo is emptied. Then, when it is desired to refill the silo, the door sections must be manually replaced, one at a time, necessitating repeated climbing of the ladder structure of the silo wall.

SUMMARY OF THE INVENTION silo door which is proof against leakage of material.

therethrough.

Still another object of this invention is the provision of a door structure which can be opened to any desired degree, so that the length of the door opening is infinitely variable between fully closed and fully opened positions of the door.

To the above ends, I provide a door frame comprising a pair of elongated side frame members having guide elements defining opposed guide channels, and adapted to be secured to the peripheral wall of a silo at opposite sides of the opening therethrough. A door comprises an elongated sheet of flexible metal having opposed longitudinal side edges each slidably received in a different one of the guide channels. The lower end of the door forming sheet is secured to a winding drum suitably journalled adjacent the lower end of the door frame, and is adapted to be wound on the drum. The upper end of the door is attached to a flexible cable which extends upwardly from the door, and which is wound on a second drum to raise the door in the guide channels toward a closed position. Operating mechanism is provided for imparting rotation to the drums selectively to move the door toward its open or closed positions.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in side elevation of a conventional silo showing the door system of this invention mounted thereon;

FIG. 2 is an enlarged fragmentary section taken on the line 22 of FIG. 1; and

FIG. 3 is a still further enlarged fragmentary transverse section taken on the line 33 of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A silo, indicated generally at 1, is shown as having a vertically elongated generally cylindrical side or peripheral wall 2 and a dome shaped roof 3, the periph- The door frame of this invention, indicated generally 7 at 6, comprises a pair of elongated vertical side frame members 7 and a plurality of vertically spaced generally horizontal cross frame members or rungs 8 that are welded or otherwise rigidly secured to the side frame members 7, the side frame members 7 being generally channel shaped, and the cross frame members 8 preferably being made of structural angle iron. Adjacent each cross frame member 8, the side frame members 7 are provided with slots 9 through which the reinforcing hoops 5 extend. Preferably, and as shown, the side frame members 7 extend vertically substantially the entire length of the peripheral silo wall 2. As shown particularly in FIGS. 2 and 3, the side frame members 4 are formed to provide flanges 10 adjacent the inner surface of the peripheral wall 2, each of the side frame members 7 being provided with cross-sectionally generally U-shaped guide elements 11 that extend longitudinally for the greater portion of the length of the side frame members 7 and are welded or otherwise rigidly secured thereto adjacent the inner flanges 10. The guide elements 11 cooperate to define opposed guide channels 12, as shown particularly in FIG. 3.

As shown in FIG. 2, the U-shaped guide elements 11 terminate at their lower ends in upwardly spaced relationship to the lower end of the silo wall 2. A transverse guide roller 13 is mounted on a shaft 14 that is journalled at its opposite ends in the side frame members 7 slightly below the lower ends of the guide elements 11. Also, preferably, and as shown in FIG. 2, a partition 15 is suitably mounted between the side frame members 7 below the guide roller 13 to provide a closure for the bottom portion of the door opening 4.

The door of this invention is indicated generally at 16, and comprises an elongated strip of longitudinally flexible imperforate sheet metal having its opposite side edges longitudinally slidably received in the guide channels 12. The door 16 has its lower end secured to a winding drum 17 mounted on a horizontally disposed shaft 18 that is journalled in a frame 19 mounted on the lower ends of the door frame members 7 by welding or other suitable means. As shown in FIG. 2, the door 16 extends from the drum 17 rearwardly and upwardly toward the lower ends of the guide elements 11, the door 16 partially encompassing theguide roller 13. At its upper end, the door 16 is reinforced by a stiffening member 20, to which is secured a loop 21. If desired, the upper end of the door may be stiffened by folding the same upon itself.

Means for raising the door 16 to a door closed position, wherein the stiffening member 20 is disposed adjacent the upper end of the door opening 4, comprises a loop engaging hook 22 secured to one end of an elongated flexible cable 23 that is entrained over a pair of pulleys 24 suitably mounted at the upper end of one of the frame members 7, the cable 23 being adapted to be wound on a second drum or reel 25 that is journalled in a framework 26 suitably mounted on the frame 19. The second drum 25 is operated to raise the door 16 to a closed position by an electric motor 27 and conventional power transmission mechanism, indicated generally at 28, which mechanism may be assumed to be operatively connected to the second drum or reel 25.

The drum 17 is rotated in a direction to pull the door 16 downwardly in the guide channels 12 by a hand crank 29 and transmission mechanism including parts not shown but contained within a gear box 30 mounted on the frame 19, a sprocket shaft 31, a sprocket wheel on the shaft 31, and an endless link chain 33 entrained over the sprocket wheel 32 and another wheel 34 mounted on the drum shaft 18, see FIG. 1.

In use, assuming that the silo is full, and the door 16 is in a closed position with the upper end thereof adjacent the upper end of the opening 4, the hook 22 is disengaged from the loop 21, after which the crank 29 is manipulated to wind a portion of the door 16 on the drum 17. This action pulls the door 16 downwardly until the upper end thereof reaches a desired level. It should here be noted that, when the hook 22 is disengaged from the loop 21, the hook 22 and adjacent end portion of the flexible cable 23 is disposed to one side or the other of the door opening 4 so that the opening 4 is unobstructed except for the cross frame members 8. As the level of silage within the silo descends, the winding drum 17 is rotated to lower the door 16 as necessary. After the silo has been emptied, and it is desired to refill the same, it is only necessary that the hook 22 be moved downwardly toward the lower end of the door opening 4 until the hook 22 may be engaged with the loop 21. Thereafter, the motor 27 is energized to wind up the cable 23 on the drum 25, thus pulling the door 16 upwardly in the guide channels 12 until the door 16 is moved to its upper limit of movement in the door opening 4. t

From the above, it will be appreciated that a great deal of time and effort is saved by the use of a unitary door such as the door 16, and the number of times an operator must the silo wall are reduced to a bare minimum. The door 16 is preferably made of metal, such as stainless steel, and is sufficiently flexible longitudinally thereof to easily run over the guide roller 13 and be wound up on the drum 17. There is sufficient rigidity in the door 16 transversely thereof to withstand the pressure of silage thereagainst from the interior of the silo.

It will be further understood that, while I haVe disclosed a manually operated winding drum l7, and a power driven winding drum 25 either thereof may be manually or power driven. Other modifications may be made without departure from the spirit and scope of the invention, as defined in the claims.

What is claimed is:

1. In a silo including a peripheral wall having inner and outer wall surfaces and defining an opening therethrough extending for the greater part of the height of said peripheral wall:

a. a vertical door frame in said opening and including a pair of elongated vertical side frame members extending substantially the length of said opening and secured to said peripheral wall at opposite sides of said opening, said side frame members defining opposed guide channels;

b. an elongated flexible metal door having a length at least equal to that of said opening and having opposite longitudinal side edges each longitudinally slidably received in a different one of said guide channels;

c. a rotary drum journaled adjacent the lower end of said door frame, the flexible door having a lower end secured to said rotary drum and adapted to be wound thereon to move the door in a downward door opening direction;

d. an elongated flexible member connected to the upper end of said flexible door and extending upwardly therefrom to a level adjacent the upper end of said opening;

e. a second drum, said flexible member being secured to said second drum for winding thereon to move said door in an upward door closing direction;

f. and means for imparting rotation to said drums selectively in opposite directions.

2. The structure defined in claim 1 in which said guide channels having lower ends upwardly spaced from the lower end of said frame, in further combination with a door engaging guide roll, journalled in said side frame members intermediate said rotary drum and the lower ends of said channels, said frame including a transverse partition extending between said side frame members at the lower ends thereof, said partition having an upper edge disposed in closely spaced relation to said guide roll to permit movement of said door between said upper edge and guide roll. 

1. In a silo including a peripheral wall having inner and outer wall surfaces and defining an opening therethrough extending for the greater part of the height of said peripheral wall: a. a vertical door frame in said opening and including a pair of elongated vertical side frame members extending substantially the length of said opening and secured to said peripheral wall at opposite sides of said opening, said side frame members defining opposed guide channels; b. an elongated flexible metal door having a length at least equal to that of said opening and having opposite longitudinal side edges each longitudinally slidably received in a different one of said guide channels; c. a rotary drum journaled adjacent the lower end of said door frame, the flexible door having a lower end secured to said rotary drum and adapted to be wound thereon to move the door in a downward door opening direction; d. an elongated flexible member connected to the upper end of said flexible door and extending upwardly therefrom to a level adjacent the upper end of said opening; e. a second drum, said flexible member being secured to said second drum for winding thereon to move said door in an upward door closing direction; f. and means for imparting rotation to said drums selectively in opposite directions.
 2. The structure defined in claim 1 in which said guide channels having lower ends upwardly spaced from the lower end of said frame, in further combination with a door engaging guide roll, journalled in said side frame members intermediate said rotary drum and the lower ends of said channels, said frame including a transverse partition extending between said side frame members at the lower ends thereof, said partition having an upper edge disposed in closely Spaced relation to said guide roll to permit movement of said door between said upper edge and guide roll. 